a. How many atoms of hydrogen are in 25.0 g of ammonia (NH3)? Use the format 6.02E+23 for 6.02 x 1023

b. How many atoms of nitrogen are in the same amount of ammonia?

How many moles in 25.0 g NH3?

moles = grams/molar mass.
There are 6.02E23 molecules in 1 mole of NH3 and there are 3 H atoms per molecule. Therefore,
6.02E23 x (25.0/molar mass) x (3 atoms H/molecule NH3) = ??

b is done the same way but there is only 1 N atom per molecule NH3.

26.572E1023

To determine the number of atoms of hydrogen and nitrogen in a given amount of ammonia (NH3), we need to use the concept of mole and Avogadro's number.

a. To find the number of hydrogen atoms in 25.0 g of ammonia (NH3), we need to follow these steps:

Step 1: Determine the molar mass of ammonia (NH3).
The molar mass of ammonia can be calculated by adding up the atomic masses of the constituent elements. Nitrogen (N) has an atomic mass of 14.01 g/mol, and hydrogen (H) has an atomic mass of 1.01 g/mol.
Molar mass of NH3 = (1.01 g/mol x 3) + 14.01 g/mol = 17.03 g/mol

Step 2: Calculate the number of moles of ammonia.
Number of moles = Given mass / Molar mass
Number of moles = 25.0 g / 17.03 g/mol ≈ 1.47 mol

Step 3: Apply Avogadro's number.
Avogadro's number represents the number of particles (atoms, molecules, etc.) in one mole of a substance. It is approximately 6.02 x 10^23.

To find the number of atoms of hydrogen, we multiply the number of moles of ammonia by the number of atoms of hydrogen per molecule of ammonia.
Number of atoms of hydrogen = Number of moles of ammonia x (number of atoms of hydrogen / number of moles of ammonia)
Number of atoms of hydrogen = 1.47 mol x (6.02 x 10^23 atoms/mol)

The answer would be written in scientific notation: 8.83 x 10^23 atoms of hydrogen.

b. Similarly, to find the number of atoms of nitrogen in the same amount (25.0 g) of ammonia, we use the same process:

Step 1: Determine the molar mass of ammonia (NH3) as calculated before (17.03 g/mol).

Step 2: Calculate the number of moles of ammonia (NH3) using the given mass (25.0 g) and molar mass (17.03 g/mol).
Number of moles = 25.0 g / 17.03 g/mol ≈ 1.47 mol

Step 3: Apply Avogadro's number.
To find the number of atoms of nitrogen, we multiply the number of moles of ammonia by the number of atoms of nitrogen per molecule of ammonia.
Number of atoms of nitrogen = Number of moles of ammonia x (number of atoms of nitrogen / number of moles of ammonia)
Number of atoms of nitrogen = 1.47 mol x (1 x 6.02 x 10^23 atoms/mol)

The answer would be written as: 8.83 x 10^23 atoms of nitrogen.